Dopamine/serotonin receptor ligands. 10: SAR Studies on azecine-type dopamine receptor ligands by functional screening at human cloned D1, D2L, and D5 receptors with a microplate reader based calcium assay lead to a novel potent D1/D5 selective antagonist

J Med Chem. 2006 Jan 26;49(2):760-9. doi: 10.1021/jm050846j.

Abstract

On the basis of the benz[d]indolo[2,3-g]azecine derivative 1 (LE300), structure-activity relations were investigated in order to identify the pharmacophore in this new class of ligands. Various structural modifications were performed and the inhibitory activities at human cloned D(1), D(2L), and D(5) receptors were measured by using a simple fluorescence microplate reader based calcium assay. Subsequently, the affinities of active compounds were estimated by radioligand binding experiments. Deleting one of the aromatic rings as well as replacing it by a phenyl moiety abolishes the inhibitory activities almost completely. Contraction of the 10-membered central ring decreases them significantly. The replacement of indole by thiophene or N-methylpyrrole reduces the inhibitory activity, whereas replacing the indole by benzene increases it. Finally, the hydroxylated dibenz[d,g]azecine derivative 11d (LE404) was found to be more active than the lead 1 in the functional calcium assay as well as in radioligand displacement experiments.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzene Derivatives / chemical synthesis
  • Benzene Derivatives / chemistry
  • Benzene Derivatives / pharmacology
  • Binding, Competitive
  • Calcium / metabolism*
  • Cell Line
  • Cloning, Molecular
  • Dopamine D2 Receptor Antagonists*
  • Fluorometry
  • Heterocyclic Compounds, 3-Ring / chemical synthesis*
  • Heterocyclic Compounds, 3-Ring / chemistry
  • Heterocyclic Compounds, 3-Ring / pharmacology
  • Humans
  • Indoles / chemical synthesis*
  • Indoles / chemistry
  • Indoles / pharmacology
  • Ligands
  • Pyrroles / chemical synthesis
  • Pyrroles / chemistry
  • Pyrroles / pharmacology
  • Radioligand Assay
  • Receptors, Dopamine D1 / antagonists & inhibitors*
  • Receptors, Dopamine D1 / metabolism
  • Receptors, Dopamine D2 / metabolism
  • Receptors, Dopamine D5 / antagonists & inhibitors*
  • Receptors, Dopamine D5 / metabolism
  • Structure-Activity Relationship
  • Thiophenes / chemical synthesis
  • Thiophenes / chemistry
  • Thiophenes / pharmacology

Substances

  • 7-methyl-2,3-dimethoxy-5,6,7,8,9,14-hexahydrodibenz(d,g)azecine
  • Benzene Derivatives
  • Dopamine D2 Receptor Antagonists
  • Heterocyclic Compounds, 3-Ring
  • Indoles
  • Ligands
  • Pyrroles
  • Receptors, Dopamine D1
  • Receptors, Dopamine D2
  • Thiophenes
  • dopamine D2L receptor
  • Receptors, Dopamine D5
  • Calcium